The invention relates to chemical compositions and their use as taggants for producing authenticatable polymers and articles, and methods for authenticating these polymers and articles. The invention is useful in security applications, particularly for authenticating articles such as security documents, pharmaceutical packaging, telecom accessories, such as cellular phone covers and batteries, and data storage media, such as compact disks (CDs) and digital versatile disks (DVDs).
A major problem confronting the various makers and users of data storage media is the unauthorized reproduction or copying of information by unauthorized manufacturers, sellers and/or users. Electronics-based and software-based approaches have been used. Piracy has evolved to the point that unauthorized duplicates now contain the original electronic anti-piracy circuit, code, etc. For example, standard holograms are now easily counterfeited and no longer guarantee the authenticity of a product. Similarly, computer codes to remove anti-piracy features and enable unlimited access to the data have been developed. Regardless of the manner, piracy of data storage media deprives legitimate software and entertainment content providers and original electronic equipment manufacturers of significant revenue and profit. Numerous approaches to thwart such consumer level piracy have been developed. One such approach involves the placement of ‘tags’ or authentication markers in substrates used in the construction of data storage media, such as those disclosed in U.S. Pat. Nos. 6,099,930, 6,514,617, 6,296,911, U.S. Patent Application No. 2002/0149003A1, and World Patent Application No. WO 00/14736.
There is also a need for chemical compositions that can be incorporated as taggants in polymer matrices through traditional processes such as molding, extrusion, and the like. In the case of engineering thermoplastics, such as polycarbonate, such processes often involve high temperatures, of the order of 280° C., or even higher. Under these high temperatures and residence times in the processing equipment, the chemical compositions known in the art generally tends to decompose or degrade, thereby leading to an unsatisfactory performance as an effective taggant in the finished polymer composition or molded article.
Therefore, there is a need for more effective and thermally stable chemical entitites, which can be used as authentication tags (or taggants) or combinations of taggants for use in polymers and articles, particularly those comprising engineering thermoplastics. It would also be desirable to provide methods for preparing such chemical compositions, and authenticating the polymer compositions and articles, such that genuine manufacturers, sellers, and/or users of the authenticatable polymer compositions and authenticatable articles are not adversely affected by unauthorized manufacturers.